diff --git a/doc/files.md b/doc/files.md
index 260d36ef3..2d3787912 100644
--- a/doc/files.md
+++ b/doc/files.md
@@ -10,3 +10,5 @@
 * fee_estimates.dat: stores statistics used to estimate minimum transaction fees and priorities required for confirmation
 * peers.dat: peer IP address database (custom format)
 * wallet.dat: personal wallet (BDB) with keys and transactions
+* .cookie: session RPC authentication cookie (written at start when cookie authentication is used, deleted on shutdown): since 0.12.0
+* onion_private_key: cached Tor hidden service private key for `-listenonion`: since 0.12.0
diff --git a/doc/tor.md b/doc/tor.md
index 61549b631..ce717515a 100644
--- a/doc/tor.md
+++ b/doc/tor.md
@@ -5,7 +5,7 @@ TOR SUPPORT IN ZCASH
 
 It is possible to run Zcash as a Tor hidden service, and connect to such services.
 
-The following directions assume you have a Tor proxy running on port 9050. Many distributions default to having a SOCKS proxy listening on port 9050, but others may not. In particular, the Tor Browser Bundle defaults to listening on a random port. See [Tor Project FAQ:TBBSocksPort](https://www.torproject.org/docs/faq.html.en#TBBSocksPort) for how to properly
+The following directions assume you have a Tor proxy running on port 9050. Many distributions default to having a SOCKS proxy listening on port 9050, but others may not. In particular, the Tor Browser Bundle defaults to listening on port 9150. See [Tor Project FAQ:TBBSocksPort](https://www.torproject.org/docs/faq.html.en#TBBSocksPort) for how to properly
 configure Tor.
 
 
@@ -72,9 +72,14 @@ In a typical situation, where you're only reachable via Tor, this should suffice
 
 	./zcashd -proxy=127.0.0.1:9050 -externalip=zctestseie6wxgio.onion -listen
 
-(obviously, replace the Onion address with your own). If you don't care too much
-about hiding your node, and want to be reachable on IPv4 as well, additionally
-specify:
+(obviously, replace the Onion address with your own). It should be noted that you still
+listen on all devices and another node could establish a clearnet connection, when knowing
+your address. To mitigate this, additionally bind the address of your Tor proxy:
+
+	./bitcoind ... -bind=127.0.0.1
+
+If you don't care too much about hiding your node, and want to be reachable on IPv4
+as well, use `discover` instead:
 
 	./zcashd ... -discover
 
@@ -86,7 +91,37 @@ for normal IPv4/IPv6 communication, use:
 	./zcashd -onion=127.0.0.1:9050 -externalip=zctestseie6wxgio.onion -discover
 
 
-3. Connect to a Zcash hidden server
+3. Automatically listen on Tor
+--------------------------------
+
+Starting with Tor version 0.2.7.1 it is possible, through Tor's control socket
+API, to create and destroy 'ephemeral' hidden services programmatically.
+Zcash has been updated to make use of this.
+
+This means that if Tor is running (and proper authentication has been configured),
+Zcash automatically creates a hidden service to listen on. Zcash will also use Tor
+automatically to connect to other .onion nodes if the control socket can be
+successfully opened. This will positively affect the number of available .onion
+nodes and their usage.
+
+This new feature is enabled by default if Zcash is listening (`-listen`), and
+requires a Tor connection to work. It can be explicitly disabled with `-listenonion=0`
+and, if not disabled, configured using the `-torcontrol` and `-torpassword` settings.
+To show verbose debugging information, pass `-debug=tor`.
+
+Connecting to Tor's control socket API requires one of two authentication methods to be 
+configured. For cookie authentication the user running zcashd must have write access 
+to the `CookieAuthFile` specified in Tor configuration. In some cases this is 
+preconfigured and the creation of a hidden service is automatic. If permission problems 
+are seen with `-debug=tor` they can be resolved by adding both the user running tor and 
+the user running zcashd to the same group and setting permissions appropriately. On 
+Debian-based systems the user running zcashd can be added to the debian-tor group, 
+which has the appropriate permissions. An alternative authentication method is the use 
+of the `-torpassword` flag and a `hash-password` which can be enabled and specified in 
+Tor configuration.
+
+
+4. Connect to a Zcash hidden server
 -----------------------------------
 
 To test your set-up, you might want to try connecting via Tor on a different computer to just a
diff --git a/qa/rpc-tests/test_framework/util.py b/qa/rpc-tests/test_framework/util.py
index 5d03403e2..f5ef9dec6 100644
--- a/qa/rpc-tests/test_framework/util.py
+++ b/qa/rpc-tests/test_framework/util.py
@@ -83,6 +83,7 @@ def initialize_datadir(dirname, n):
         f.write("rpcpassword=rt\n");
         f.write("port="+str(p2p_port(n))+"\n");
         f.write("rpcport="+str(rpc_port(n))+"\n");
+        f.write("listenonion=0\n");
     return datadir
 
 def initialize_chain(test_dir):
diff --git a/src/Makefile.am b/src/Makefile.am
index 33c1fba2d..9963f2858 100644
--- a/src/Makefile.am
+++ b/src/Makefile.am
@@ -164,6 +164,7 @@ BITCOIN_CORE_H = \
   threadsafety.h \
   timedata.h \
   tinyformat.h \
+  torcontrol.h \
   txdb.h \
   txmempool.h \
   ui_interface.h \
@@ -227,6 +228,7 @@ libbitcoin_server_a_SOURCES = \
   rpcserver.cpp \
   script/sigcache.cpp \
   timedata.cpp \
+  torcontrol.cpp \
   txdb.cpp \
   txmempool.cpp \
   validationinterface.cpp \
diff --git a/src/Makefile.test.include b/src/Makefile.test.include
index 7de8c392f..c97ea692d 100644
--- a/src/Makefile.test.include
+++ b/src/Makefile.test.include
@@ -84,6 +84,7 @@ BITCOIN_TESTS =\
   test/test_bitcoin.cpp \
   test/test_bitcoin.h \
   test/timedata_tests.cpp \
+  test/torcontrol_tests.cpp \
   test/transaction_tests.cpp \
   test/uint256_tests.cpp \
   test/univalue_tests.cpp \
@@ -100,7 +101,7 @@ endif
 test_test_bitcoin_SOURCES = $(BITCOIN_TESTS) $(JSON_TEST_FILES) $(RAW_TEST_FILES)
 test_test_bitcoin_CPPFLAGS = -fopenmp $(BITCOIN_INCLUDES) -I$(builddir)/test/ $(TESTDEFS) $(EVENT_CFLAGS)
 test_test_bitcoin_LDADD = $(LIBBITCOIN_SERVER) $(LIBBITCOIN_CLI) $(LIBBITCOIN_COMMON) $(LIBBITCOIN_UTIL) $(LIBBITCOIN_CRYPTO) $(LIBUNIVALUE) $(LIBLEVELDB) $(LIBMEMENV) \
-  $(BOOST_LIBS) $(BOOST_UNIT_TEST_FRAMEWORK_LIB) $(LIBSECP256K1) $(EVENT_LIBS)
+  $(BOOST_LIBS) $(BOOST_UNIT_TEST_FRAMEWORK_LIB) $(LIBSECP256K1) $(EVENT_PTHREADS_LIBS) $(EVENT_LIBS)
 if ENABLE_WALLET
 test_test_bitcoin_LDADD += $(LIBBITCOIN_WALLET)
 endif
diff --git a/src/init.cpp b/src/init.cpp
index 66f7005eb..ec3553c46 100644
--- a/src/init.cpp
+++ b/src/init.cpp
@@ -28,6 +28,7 @@
 #include "script/standard.h"
 #include "scheduler.h"
 #include "txdb.h"
+#include "torcontrol.h"
 #include "ui_interface.h"
 #include "util.h"
 #include "utilmoneystr.h"
@@ -159,6 +160,7 @@ void Interrupt(boost::thread_group& threadGroup)
     InterruptHTTPRPC();
     InterruptRPC();
     InterruptREST();
+    InterruptTorControl();
     threadGroup.interrupt_all();
 }
 
@@ -193,6 +195,7 @@ void Shutdown()
  #endif
 #endif
     StopNode();
+    StopTorControl();
     UnregisterNodeSignals(GetNodeSignals());
 
     if (fFeeEstimatesInitialized)
@@ -355,7 +358,8 @@ std::string HelpMessage(HelpMessageMode mode)
     strUsage += HelpMessageOpt("-externalip=<ip>", _("Specify your own public address"));
     strUsage += HelpMessageOpt("-forcednsseed", strprintf(_("Always query for peer addresses via DNS lookup (default: %u)"), 0));
     strUsage += HelpMessageOpt("-listen", _("Accept connections from outside (default: 1 if no -proxy or -connect)"));
-    strUsage += HelpMessageOpt("-maxconnections=<n>", strprintf(_("Maintain at most <n> connections to peers (default: %u)"), 125));
+    strUsage += HelpMessageOpt("-listenonion", strprintf(_("Automatically create Tor hidden service (default: %d)"), DEFAULT_LISTEN_ONION));
+    strUsage += HelpMessageOpt("-maxconnections=<n>", strprintf(_("Maintain at most <n> connections to peers (default: %u)"), DEFAULT_MAX_PEER_CONNECTIONS));
     strUsage += HelpMessageOpt("-maxreceivebuffer=<n>", strprintf(_("Maximum per-connection receive buffer, <n>*1000 bytes (default: %u)"), 5000));
     strUsage += HelpMessageOpt("-maxsendbuffer=<n>", strprintf(_("Maximum per-connection send buffer, <n>*1000 bytes (default: %u)"), 1000));
     strUsage += HelpMessageOpt("-onion=<ip:port>", strprintf(_("Use separate SOCKS5 proxy to reach peers via Tor hidden services (default: %s)"), "-proxy"));
@@ -366,6 +370,8 @@ std::string HelpMessage(HelpMessageMode mode)
     strUsage += HelpMessageOpt("-proxyrandomize", strprintf(_("Randomize credentials for every proxy connection. This enables Tor stream isolation (default: %u)"), 1));
     strUsage += HelpMessageOpt("-seednode=<ip>", _("Connect to a node to retrieve peer addresses, and disconnect"));
     strUsage += HelpMessageOpt("-timeout=<n>", strprintf(_("Specify connection timeout in milliseconds (minimum: 1, default: %d)"), DEFAULT_CONNECT_TIMEOUT));
+    strUsage += HelpMessageOpt("-torcontrol=<ip>:<port>", strprintf(_("Tor control port to use if onion listening enabled (default: %s)"), DEFAULT_TOR_CONTROL));
+    strUsage += HelpMessageOpt("-torpassword=<pass>", _("Tor control port password (default: empty)"));
 #ifdef USE_UPNP
 #if USE_UPNP
     strUsage += HelpMessageOpt("-upnp", _("Use UPnP to map the listening port (default: 1 when listening and no -proxy)"));
@@ -421,7 +427,7 @@ std::string HelpMessage(HelpMessageMode mode)
         strUsage += HelpMessageOpt("-stopafterblockimport", strprintf("Stop running after importing blocks from disk (default: %u)", 0));
     }
     string debugCategories = "addrman, alert, bench, coindb, db, estimatefee, http, libevent, lock, mempool, net, partitioncheck, pow, proxy, prune, "
-                             "rand, reindex, rpc, selectcoins, zmq, zrpc, zrpcunsafe (implies zrpc)"; // Don't translate these
+                             "rand, reindex, rpc, selectcoins, tor, zmq, zrpc, zrpcunsafe (implies zrpc)"; // Don't translate these
     strUsage += HelpMessageOpt("-debug=<category>", strprintf(_("Output debugging information (default: %u, supplying <category> is optional)"), 0) + ". " +
         _("If <category> is not supplied or if <category> = 1, output all debugging information.") + " " + _("<category> can be:") + " " + debugCategories + ".");
     strUsage += HelpMessageOpt("-experimentalfeatures", _("Enable use of experimental features"));
@@ -810,6 +816,8 @@ bool AppInit2(boost::thread_group& threadGroup, CScheduler& scheduler)
             LogPrintf("%s: parameter interaction: -listen=0 -> setting -upnp=0\n", __func__);
         if (SoftSetBoolArg("-discover", false))
             LogPrintf("%s: parameter interaction: -listen=0 -> setting -discover=0\n", __func__);
+        if (SoftSetBoolArg("-listenonion", false))
+            LogPrintf("%s: parameter interaction: -listen=0 -> setting -listenonion=0\n", __func__);
     }
 
     if (mapArgs.count("-externalip")) {
@@ -832,7 +840,7 @@ bool AppInit2(boost::thread_group& threadGroup, CScheduler& scheduler)
 
     // Make sure enough file descriptors are available
     int nBind = std::max((int)mapArgs.count("-bind") + (int)mapArgs.count("-whitebind"), 1);
-    nMaxConnections = GetArg("-maxconnections", 125);
+    nMaxConnections = GetArg("-maxconnections", DEFAULT_MAX_PEER_CONNECTIONS);
     nMaxConnections = std::max(std::min(nMaxConnections, (int)(FD_SETSIZE - nBind - MIN_CORE_FILEDESCRIPTORS)), 0);
     int nFD = RaiseFileDescriptorLimit(nMaxConnections + MIN_CORE_FILEDESCRIPTORS);
     if (nFD < MIN_CORE_FILEDESCRIPTORS)
@@ -1149,6 +1157,7 @@ bool AppInit2(boost::thread_group& threadGroup, CScheduler& scheduler)
     // -proxy sets a proxy for all outgoing network traffic
     // -noproxy (or -proxy=0) as well as the empty string can be used to not set a proxy, this is the default
     std::string proxyArg = GetArg("-proxy", "");
+    SetLimited(NET_TOR);
     if (proxyArg != "" && proxyArg != "0") {
         proxyType addrProxy = proxyType(CService(proxyArg, 9050), proxyRandomize);
         if (!addrProxy.IsValid())
@@ -1158,7 +1167,7 @@ bool AppInit2(boost::thread_group& threadGroup, CScheduler& scheduler)
         SetProxy(NET_IPV6, addrProxy);
         SetProxy(NET_TOR, addrProxy);
         SetNameProxy(addrProxy);
-        SetReachable(NET_TOR); // by default, -proxy sets onion as reachable, unless -noonion later
+        SetLimited(NET_TOR, false); // by default, -proxy sets onion as reachable, unless -noonion later
     }
 
     // -onion can be used to set only a proxy for .onion, or override normal proxy for .onion addresses
@@ -1167,13 +1176,13 @@ bool AppInit2(boost::thread_group& threadGroup, CScheduler& scheduler)
     std::string onionArg = GetArg("-onion", "");
     if (onionArg != "") {
         if (onionArg == "0") { // Handle -noonion/-onion=0
-            SetReachable(NET_TOR, false); // set onions as unreachable
+            SetLimited(NET_TOR); // set onions as unreachable
         } else {
             proxyType addrOnion = proxyType(CService(onionArg, 9050), proxyRandomize);
             if (!addrOnion.IsValid())
                 return InitError(strprintf(_("Invalid -onion address: '%s'"), onionArg));
             SetProxy(NET_TOR, addrOnion);
-            SetReachable(NET_TOR);
+            SetLimited(NET_TOR, false);
         }
     }
 
@@ -1614,6 +1623,9 @@ bool AppInit2(boost::thread_group& threadGroup, CScheduler& scheduler)
     LogPrintf("mapAddressBook.size() = %u\n",  pwalletMain ? pwalletMain->mapAddressBook.size() : 0);
 #endif
 
+    if (GetBoolArg("-listenonion", DEFAULT_LISTEN_ONION))
+        StartTorControl(threadGroup, scheduler);
+
     StartNode(threadGroup, scheduler);
 
     // Monitor the chain, and alert if we get blocks much quicker or slower than expected
diff --git a/src/main.cpp b/src/main.cpp
index 438dcc425..ab91ee41e 100644
--- a/src/main.cpp
+++ b/src/main.cpp
@@ -4402,9 +4402,11 @@ bool static ProcessMessage(CNode* pfrom, string strCommand, CDataStream& vRecv,
                 CAddress addr = GetLocalAddress(&pfrom->addr);
                 if (addr.IsRoutable())
                 {
+                    LogPrintf("ProcessMessages: advertizing address %s\n", addr.ToString());
                     pfrom->PushAddress(addr);
                 } else if (IsPeerAddrLocalGood(pfrom)) {
                     addr.SetIP(pfrom->addrLocal);
+                    LogPrintf("ProcessMessages: advertizing address %s\n", addr.ToString());
                     pfrom->PushAddress(addr);
                 }
             }
diff --git a/src/net.cpp b/src/net.cpp
index ed22cf324..de624c72a 100644
--- a/src/net.cpp
+++ b/src/net.cpp
@@ -72,13 +72,12 @@ bool fListen = true;
 uint64_t nLocalServices = NODE_NETWORK;
 CCriticalSection cs_mapLocalHost;
 map<CNetAddr, LocalServiceInfo> mapLocalHost;
-static bool vfReachable[NET_MAX] = {};
 static bool vfLimited[NET_MAX] = {};
 static CNode* pnodeLocalHost = NULL;
 uint64_t nLocalHostNonce = 0;
 static std::vector<ListenSocket> vhListenSocket;
 CAddrMan addrman;
-int nMaxConnections = 125;
+int nMaxConnections = DEFAULT_MAX_PEER_CONNECTIONS;
 bool fAddressesInitialized = false;
 
 vector<CNode*> vNodes;
@@ -212,19 +211,12 @@ void AdvertizeLocal(CNode *pnode)
         }
         if (addrLocal.IsRoutable())
         {
+            LogPrintf("AdvertizeLocal: advertizing address %s\n", addrLocal.ToString());
             pnode->PushAddress(addrLocal);
         }
     }
 }
 
-void SetReachable(enum Network net, bool fFlag)
-{
-    LOCK(cs_mapLocalHost);
-    vfReachable[net] = fFlag;
-    if (net == NET_IPV6 && fFlag)
-        vfReachable[NET_IPV4] = true;
-}
-
 // learn a new local address
 bool AddLocal(const CService& addr, int nScore)
 {
@@ -247,7 +239,6 @@ bool AddLocal(const CService& addr, int nScore)
             info.nScore = nScore + (fAlready ? 1 : 0);
             info.nPort = addr.GetPort();
         }
-        SetReachable(addr.GetNetwork());
     }
 
     return true;
@@ -258,6 +249,14 @@ bool AddLocal(const CNetAddr &addr, int nScore)
     return AddLocal(CService(addr, GetListenPort()), nScore);
 }
 
+bool RemoveLocal(const CService& addr)
+{
+    LOCK(cs_mapLocalHost);
+    LogPrintf("RemoveLocal(%s)\n", addr.ToString());
+    mapLocalHost.erase(addr);
+    return true;
+}
+
 /** Make a particular network entirely off-limits (no automatic connects to it) */
 void SetLimited(enum Network net, bool fLimited)
 {
@@ -302,7 +301,7 @@ bool IsLocal(const CService& addr)
 bool IsReachable(enum Network net)
 {
     LOCK(cs_mapLocalHost);
-    return vfReachable[net] && !vfLimited[net];
+    return !vfLimited[net];
 }
 
 /** check whether a given address is in a network we can probably connect to */
@@ -812,8 +811,6 @@ static bool AttemptToEvictConnection(bool fPreferNewConnection) {
                 continue;
             if (node->fDisconnect)
                 continue;
-            if (node->addr.IsLocal())
-                continue;
             vEvictionCandidates.push_back(CNodeRef(node));
         }
     }
@@ -844,15 +841,20 @@ static bool AttemptToEvictConnection(bool fPreferNewConnection) {
 
     if (vEvictionCandidates.empty()) return false;
 
-    // Identify the network group with the most connections
+    // Identify the network group with the most connections and youngest member.
+    // (vEvictionCandidates is already sorted by reverse connect time)
     std::vector<unsigned char> naMostConnections;
     unsigned int nMostConnections = 0;
+    int64_t nMostConnectionsTime = 0;
     std::map<std::vector<unsigned char>, std::vector<CNodeRef> > mapAddrCounts;
     BOOST_FOREACH(const CNodeRef &node, vEvictionCandidates) {
         mapAddrCounts[node->addr.GetGroup()].push_back(node);
+        int64_t grouptime = mapAddrCounts[node->addr.GetGroup()][0]->nTimeConnected;
+        size_t groupsize = mapAddrCounts[node->addr.GetGroup()].size();
 
-        if (mapAddrCounts[node->addr.GetGroup()].size() > nMostConnections) {
-            nMostConnections = mapAddrCounts[node->addr.GetGroup()].size();
+        if (groupsize > nMostConnections || (groupsize == nMostConnections && grouptime > nMostConnectionsTime)) {
+            nMostConnections = groupsize;
+            nMostConnectionsTime = grouptime;
             naMostConnections = node->addr.GetGroup();
         }
     }
@@ -860,14 +862,13 @@ static bool AttemptToEvictConnection(bool fPreferNewConnection) {
     // Reduce to the network group with the most connections
     vEvictionCandidates = mapAddrCounts[naMostConnections];
 
-    // Do not disconnect peers if there is only 1 connection from their network group
+    // Do not disconnect peers if there is only one unprotected connection from their network group.
     if (vEvictionCandidates.size() <= 1)
         // unless we prefer the new connection (for whitelisted peers)
         if (!fPreferNewConnection)
             return false;
 
-    // Disconnect the most recent connection from the network group with the most connections
-    std::sort(vEvictionCandidates.begin(), vEvictionCandidates.end(), ReverseCompareNodeTimeConnected);
+    // Disconnect from the network group with the most connections
     vEvictionCandidates[0]->fDisconnect = true;
 
     return true;
diff --git a/src/net.h b/src/net.h
index 720763506..f7ebf11f6 100644
--- a/src/net.h
+++ b/src/net.h
@@ -61,6 +61,8 @@ static const bool DEFAULT_UPNP = false;
 static const size_t MAPASKFOR_MAX_SZ = MAX_INV_SZ;
 /** The maximum number of entries in setAskFor (larger due to getdata latency)*/
 static const size_t SETASKFOR_MAX_SZ = 2 * MAX_INV_SZ;
+/** The maximum number of peer connections to maintain. */
+static const unsigned int DEFAULT_MAX_PEER_CONNECTIONS = 125;
 
 unsigned int ReceiveFloodSize();
 unsigned int SendBufferSize();
@@ -129,12 +131,12 @@ bool IsLimited(enum Network net);
 bool IsLimited(const CNetAddr& addr);
 bool AddLocal(const CService& addr, int nScore = LOCAL_NONE);
 bool AddLocal(const CNetAddr& addr, int nScore = LOCAL_NONE);
+bool RemoveLocal(const CService& addr);
 bool SeenLocal(const CService& addr);
 bool IsLocal(const CService& addr);
 bool GetLocal(CService &addr, const CNetAddr *paddrPeer = NULL);
 bool IsReachable(enum Network net);
 bool IsReachable(const CNetAddr &addr);
-void SetReachable(enum Network net, bool fFlag = true);
 CAddress GetLocalAddress(const CNetAddr *paddrPeer = NULL);
 
 
diff --git a/src/netbase.cpp b/src/netbase.cpp
index 8ff621942..c88a227fd 100644
--- a/src/netbase.cpp
+++ b/src/netbase.cpp
@@ -227,10 +227,7 @@ bool LookupNumeric(const char *pszName, CService& addr, int portDefault)
     return Lookup(pszName, addr, portDefault, false);
 }
 
-/**
- * Convert milliseconds to a struct timeval for select.
- */
-struct timeval static MillisToTimeval(int64_t nTimeout)
+struct timeval MillisToTimeval(int64_t nTimeout)
 {
     struct timeval timeout;
     timeout.tv_sec  = nTimeout / 1000;
diff --git a/src/netbase.h b/src/netbase.h
index 27f0eac2a..21ac0aa4c 100644
--- a/src/netbase.h
+++ b/src/netbase.h
@@ -203,5 +203,9 @@ std::string NetworkErrorString(int err);
 bool CloseSocket(SOCKET& hSocket);
 /** Disable or enable blocking-mode for a socket */
 bool SetSocketNonBlocking(SOCKET& hSocket, bool fNonBlocking);
+/**
+ * Convert milliseconds to a struct timeval for e.g. select.
+ */
+struct timeval MillisToTimeval(int64_t nTimeout);
 
 #endif // BITCOIN_NETBASE_H
diff --git a/src/streams.h b/src/streams.h
index 9b678b3c0..81b58fd05 100644
--- a/src/streams.h
+++ b/src/streams.h
@@ -295,8 +295,8 @@ public:
         return (*this);
     }
 
-    void GetAndClear(CSerializeData &data) {
-        data.insert(data.end(), begin(), end());
+    void GetAndClear(CSerializeData &d) {
+        d.insert(d.end(), begin(), end());
         clear();
     }
 };
diff --git a/src/test/torcontrol_tests.cpp b/src/test/torcontrol_tests.cpp
new file mode 100644
index 000000000..68516599d
--- /dev/null
+++ b/src/test/torcontrol_tests.cpp
@@ -0,0 +1,168 @@
+// Copyright (c) 2017 The Zcash developers
+// Distributed under the MIT software license, see the accompanying
+// file COPYING or http://www.opensource.org/licenses/mit-license.php.
+//
+#include "test/test_bitcoin.h"
+#include "torcontrol.cpp"
+
+#include <boost/test/unit_test.hpp>
+
+
+BOOST_FIXTURE_TEST_SUITE(torcontrol_tests, BasicTestingSetup)
+
+void CheckSplitTorReplyLine(std::string input, std::string command, std::string args)
+{
+    BOOST_TEST_MESSAGE(std::string("CheckSplitTorReplyLine(") + input + ")");
+    auto ret = SplitTorReplyLine(input);
+    BOOST_CHECK_EQUAL(ret.first, command);
+    BOOST_CHECK_EQUAL(ret.second, args);
+}
+
+BOOST_AUTO_TEST_CASE(util_SplitTorReplyLine)
+{
+    // Data we should receive during normal usage
+    CheckSplitTorReplyLine(
+        "PROTOCOLINFO PIVERSION",
+        "PROTOCOLINFO", "PIVERSION");
+    CheckSplitTorReplyLine(
+        "AUTH METHODS=COOKIE,SAFECOOKIE COOKIEFILE=\"/home/x/.tor/control_auth_cookie\"",
+        "AUTH", "METHODS=COOKIE,SAFECOOKIE COOKIEFILE=\"/home/x/.tor/control_auth_cookie\"");
+    CheckSplitTorReplyLine(
+        "AUTH METHODS=NULL",
+        "AUTH", "METHODS=NULL");
+    CheckSplitTorReplyLine(
+        "AUTH METHODS=HASHEDPASSWORD",
+        "AUTH", "METHODS=HASHEDPASSWORD");
+    CheckSplitTorReplyLine(
+        "VERSION Tor=\"0.2.9.8 (git-a0df013ea241b026)\"",
+        "VERSION", "Tor=\"0.2.9.8 (git-a0df013ea241b026)\"");
+    CheckSplitTorReplyLine(
+        "AUTHCHALLENGE SERVERHASH=aaaa SERVERNONCE=bbbb",
+        "AUTHCHALLENGE", "SERVERHASH=aaaa SERVERNONCE=bbbb");
+
+    // Other valid inputs
+    CheckSplitTorReplyLine("COMMAND", "COMMAND", "");
+    CheckSplitTorReplyLine("COMMAND SOME  ARGS", "COMMAND", "SOME  ARGS");
+
+    // These inputs are valid because PROTOCOLINFO accepts an OtherLine that is
+    // just an OptArguments, which enables multiple spaces to be present
+    // between the command and arguments.
+    CheckSplitTorReplyLine("COMMAND  ARGS", "COMMAND", " ARGS");
+    CheckSplitTorReplyLine("COMMAND   EVEN+more  ARGS", "COMMAND", "  EVEN+more  ARGS");
+}
+
+void CheckParseTorReplyMapping(std::string input, std::map<std::string,std::string> expected)
+{
+    BOOST_TEST_MESSAGE(std::string("CheckParseTorReplyMapping(") + input + ")");
+    auto ret = ParseTorReplyMapping(input);
+    BOOST_CHECK_EQUAL(ret.size(), expected.size());
+    auto r_it = ret.begin();
+    auto e_it = expected.begin();
+    while (r_it != ret.end() && e_it != expected.end()) {
+        BOOST_CHECK_EQUAL(r_it->first, e_it->first);
+        BOOST_CHECK_EQUAL(r_it->second, e_it->second);
+        r_it++;
+        e_it++;
+    }
+}
+
+BOOST_AUTO_TEST_CASE(util_ParseTorReplyMapping)
+{
+    // Data we should receive during normal usage
+    CheckParseTorReplyMapping(
+        "METHODS=COOKIE,SAFECOOKIE COOKIEFILE=\"/home/x/.tor/control_auth_cookie\"", {
+            {"METHODS", "COOKIE,SAFECOOKIE"},
+            {"COOKIEFILE", "/home/x/.tor/control_auth_cookie"},
+        });
+    CheckParseTorReplyMapping(
+        "METHODS=NULL", {
+            {"METHODS", "NULL"},
+        });
+    CheckParseTorReplyMapping(
+        "METHODS=HASHEDPASSWORD", {
+            {"METHODS", "HASHEDPASSWORD"},
+        });
+    CheckParseTorReplyMapping(
+        "Tor=\"0.2.9.8 (git-a0df013ea241b026)\"", {
+            {"Tor", "0.2.9.8 (git-a0df013ea241b026)"},
+        });
+    CheckParseTorReplyMapping(
+        "SERVERHASH=aaaa SERVERNONCE=bbbb", {
+            {"SERVERHASH", "aaaa"},
+            {"SERVERNONCE", "bbbb"},
+        });
+    CheckParseTorReplyMapping(
+        "ServiceID=exampleonion1234", {
+            {"ServiceID", "exampleonion1234"},
+        });
+    CheckParseTorReplyMapping(
+        "PrivateKey=RSA1024:BLOB", {
+            {"PrivateKey", "RSA1024:BLOB"},
+        });
+    CheckParseTorReplyMapping(
+        "ClientAuth=bob:BLOB", {
+            {"ClientAuth", "bob:BLOB"},
+        });
+
+    // Other valid inputs
+    CheckParseTorReplyMapping(
+        "Foo=Bar=Baz Spam=Eggs", {
+            {"Foo", "Bar=Baz"},
+            {"Spam", "Eggs"},
+        });
+    CheckParseTorReplyMapping(
+        "Foo=\"Bar=Baz\"", {
+            {"Foo", "Bar=Baz"},
+        });
+    CheckParseTorReplyMapping(
+        "Foo=\"Bar Baz\"", {
+            {"Foo", "Bar Baz"},
+        });
+
+    // Escapes (which are left escaped by the parser)
+    CheckParseTorReplyMapping(
+        "Foo=\"Bar\\ Baz\"", {
+            {"Foo", "Bar\\ Baz"},
+        });
+    CheckParseTorReplyMapping(
+        "Foo=\"Bar\\Baz\"", {
+            {"Foo", "Bar\\Baz"},
+        });
+    CheckParseTorReplyMapping(
+        "Foo=\"Bar\\@Baz\"", {
+            {"Foo", "Bar\\@Baz"},
+        });
+    CheckParseTorReplyMapping(
+        "Foo=\"Bar\\\"Baz\" Spam=\"\\\"Eggs\\\"\"", {
+            {"Foo", "Bar\\\"Baz"},
+            {"Spam", "\\\"Eggs\\\""},
+        });
+    CheckParseTorReplyMapping(
+        "Foo=\"Bar\\\\Baz\"", {
+            {"Foo", "Bar\\\\Baz"},
+        });
+
+    // A more complex valid grammar. PROTOCOLINFO accepts a VersionLine that
+    // takes a key=value pair followed by an OptArguments, making this valid.
+    // Because an OptArguments contains no semantic data, there is no point in
+    // parsing it.
+    CheckParseTorReplyMapping(
+        "SOME=args,here MORE optional=arguments  here", {
+            {"SOME", "args,here"},
+        });
+
+    // Inputs that are effectively invalid under the target grammar.
+    // PROTOCOLINFO accepts an OtherLine that is just an OptArguments, which
+    // would make these inputs valid. However,
+    // - This parser is never used in that situation, because the
+    //   SplitTorReplyLine parser enables OtherLine to be skipped.
+    // - Even if these were valid, an OptArguments contains no semantic data,
+    //   so there is no point in parsing it.
+    CheckParseTorReplyMapping("ARGS", {});
+    CheckParseTorReplyMapping("MORE ARGS", {});
+    CheckParseTorReplyMapping("MORE  ARGS", {});
+    CheckParseTorReplyMapping("EVEN more=ARGS", {});
+    CheckParseTorReplyMapping("EVEN+more ARGS", {});
+}
+
+BOOST_AUTO_TEST_SUITE_END()
diff --git a/src/torcontrol.cpp b/src/torcontrol.cpp
new file mode 100644
index 000000000..60181b440
--- /dev/null
+++ b/src/torcontrol.cpp
@@ -0,0 +1,726 @@
+#include "torcontrol.h"
+#include "utilstrencodings.h"
+#include "net.h"
+#include "util.h"
+#include "crypto/hmac_sha256.h"
+
+#include <vector>
+#include <deque>
+#include <set>
+#include <stdlib.h>
+
+#include <boost/function.hpp>
+#include <boost/bind.hpp>
+#include <boost/signals2/signal.hpp>
+#include <boost/foreach.hpp>
+#include <boost/algorithm/string/predicate.hpp>
+#include <boost/algorithm/string/split.hpp>
+#include <boost/algorithm/string/classification.hpp>
+#include <boost/algorithm/string/replace.hpp>
+
+#include <event2/bufferevent.h>
+#include <event2/buffer.h>
+#include <event2/util.h>
+#include <event2/event.h>
+#include <event2/thread.h>
+
+/** Default control port */
+const std::string DEFAULT_TOR_CONTROL = "127.0.0.1:9051";
+/** Tor cookie size (from control-spec.txt) */
+static const int TOR_COOKIE_SIZE = 32;
+/** Size of client/server nonce for SAFECOOKIE */
+static const int TOR_NONCE_SIZE = 32;
+/** For computing serverHash in SAFECOOKIE */
+static const std::string TOR_SAFE_SERVERKEY = "Tor safe cookie authentication server-to-controller hash";
+/** For computing clientHash in SAFECOOKIE */
+static const std::string TOR_SAFE_CLIENTKEY = "Tor safe cookie authentication controller-to-server hash";
+/** Exponential backoff configuration - initial timeout in seconds */
+static const float RECONNECT_TIMEOUT_START = 1.0;
+/** Exponential backoff configuration - growth factor */
+static const float RECONNECT_TIMEOUT_EXP = 1.5;
+/** Maximum length for lines received on TorControlConnection.
+ * tor-control-spec.txt mentions that there is explicitly no limit defined to line length,
+ * this is belt-and-suspenders sanity limit to prevent memory exhaustion.
+ */
+static const int MAX_LINE_LENGTH = 100000;
+
+/****** Low-level TorControlConnection ********/
+
+/** Reply from Tor, can be single or multi-line */
+class TorControlReply
+{
+public:
+    TorControlReply() { Clear(); }
+
+    int code;
+    std::vector<std::string> lines;
+
+    void Clear()
+    {
+        code = 0;
+        lines.clear();
+    }
+};
+
+/** Low-level handling for Tor control connection.
+ * Speaks the SMTP-like protocol as defined in torspec/control-spec.txt
+ */
+class TorControlConnection
+{
+public:
+    typedef boost::function<void(TorControlConnection&)> ConnectionCB;
+    typedef boost::function<void(TorControlConnection &,const TorControlReply &)> ReplyHandlerCB;
+
+    /** Create a new TorControlConnection.
+     */
+    TorControlConnection(struct event_base *base);
+    ~TorControlConnection();
+
+    /**
+     * Connect to a Tor control port.
+     * target is address of the form host:port.
+     * connected is the handler that is called when connection is successfully established.
+     * disconnected is a handler that is called when the connection is broken.
+     * Return true on success.
+     */
+    bool Connect(const std::string &target, const ConnectionCB& connected, const ConnectionCB& disconnected);
+
+    /**
+     * Disconnect from Tor control port.
+     */
+    bool Disconnect();
+
+    /** Send a command, register a handler for the reply.
+     * A trailing CRLF is automatically added.
+     * Return true on success.
+     */
+    bool Command(const std::string &cmd, const ReplyHandlerCB& reply_handler);
+
+    /** Response handlers for async replies */
+    boost::signals2::signal<void(TorControlConnection &,const TorControlReply &)> async_handler;
+private:
+    /** Callback when ready for use */
+    boost::function<void(TorControlConnection&)> connected;
+    /** Callback when connection lost */
+    boost::function<void(TorControlConnection&)> disconnected;
+    /** Libevent event base */
+    struct event_base *base;
+    /** Connection to control socket */
+    struct bufferevent *b_conn;
+    /** Message being received */
+    TorControlReply message;
+    /** Response handlers */
+    std::deque<ReplyHandlerCB> reply_handlers;
+
+    /** Libevent handlers: internal */
+    static void readcb(struct bufferevent *bev, void *ctx);
+    static void eventcb(struct bufferevent *bev, short what, void *ctx);
+};
+
+TorControlConnection::TorControlConnection(struct event_base *base):
+    base(base), b_conn(0)
+{
+}
+
+TorControlConnection::~TorControlConnection()
+{
+    if (b_conn)
+        bufferevent_free(b_conn);
+}
+
+void TorControlConnection::readcb(struct bufferevent *bev, void *ctx)
+{
+    TorControlConnection *self = (TorControlConnection*)ctx;
+    struct evbuffer *input = bufferevent_get_input(bev);
+    size_t n_read_out = 0;
+    char *line;
+    assert(input);
+    //  If there is not a whole line to read, evbuffer_readln returns NULL
+    while((line = evbuffer_readln(input, &n_read_out, EVBUFFER_EOL_CRLF)) != NULL)
+    {
+        std::string s(line, n_read_out);
+        free(line);
+        if (s.size() < 4) // Short line
+            continue;
+        // <status>(-|+| )<data><CRLF>
+        self->message.code = atoi(s.substr(0,3));
+        self->message.lines.push_back(s.substr(4));
+        char ch = s[3]; // '-','+' or ' '
+        if (ch == ' ') {
+            // Final line, dispatch reply and clean up
+            if (self->message.code >= 600) {
+                // Dispatch async notifications to async handler
+                // Synchronous and asynchronous messages are never interleaved
+                self->async_handler(*self, self->message);
+            } else {
+                if (!self->reply_handlers.empty()) {
+                    // Invoke reply handler with message
+                    self->reply_handlers.front()(*self, self->message);
+                    self->reply_handlers.pop_front();
+                } else {
+                    LogPrint("tor", "tor: Received unexpected sync reply %i\n", self->message.code);
+                }
+            }
+            self->message.Clear();
+        }
+    }
+    //  Check for size of buffer - protect against memory exhaustion with very long lines
+    //  Do this after evbuffer_readln to make sure all full lines have been
+    //  removed from the buffer. Everything left is an incomplete line.
+    if (evbuffer_get_length(input) > MAX_LINE_LENGTH) {
+        LogPrintf("tor: Disconnecting because MAX_LINE_LENGTH exceeded\n");
+        self->Disconnect();
+    }
+}
+
+void TorControlConnection::eventcb(struct bufferevent *bev, short what, void *ctx)
+{
+    TorControlConnection *self = (TorControlConnection*)ctx;
+    if (what & BEV_EVENT_CONNECTED) {
+        LogPrint("tor", "tor: Successfully connected!\n");
+        self->connected(*self);
+    } else if (what & (BEV_EVENT_EOF|BEV_EVENT_ERROR)) {
+        if (what & BEV_EVENT_ERROR)
+            LogPrint("tor", "tor: Error connecting to Tor control socket\n");
+        else
+            LogPrint("tor", "tor: End of stream\n");
+        self->Disconnect();
+        self->disconnected(*self);
+    }
+}
+
+bool TorControlConnection::Connect(const std::string &target, const ConnectionCB& connected, const ConnectionCB& disconnected)
+{
+    if (b_conn)
+        Disconnect();
+    // Parse target address:port
+    struct sockaddr_storage connect_to_addr;
+    int connect_to_addrlen = sizeof(connect_to_addr);
+    if (evutil_parse_sockaddr_port(target.c_str(),
+        (struct sockaddr*)&connect_to_addr, &connect_to_addrlen)<0) {
+        LogPrintf("tor: Error parsing socket address %s\n", target);
+        return false;
+    }
+
+    // Create a new socket, set up callbacks and enable notification bits
+    b_conn = bufferevent_socket_new(base, -1, BEV_OPT_CLOSE_ON_FREE);
+    if (!b_conn)
+        return false;
+    bufferevent_setcb(b_conn, TorControlConnection::readcb, NULL, TorControlConnection::eventcb, this);
+    bufferevent_enable(b_conn, EV_READ|EV_WRITE);
+    this->connected = connected;
+    this->disconnected = disconnected;
+
+    // Finally, connect to target
+    if (bufferevent_socket_connect(b_conn, (struct sockaddr*)&connect_to_addr, connect_to_addrlen) < 0) {
+        LogPrintf("tor: Error connecting to address %s\n", target);
+        return false;
+    }
+    return true;
+}
+
+bool TorControlConnection::Disconnect()
+{
+    if (b_conn)
+        bufferevent_free(b_conn);
+    b_conn = 0;
+    return true;
+}
+
+bool TorControlConnection::Command(const std::string &cmd, const ReplyHandlerCB& reply_handler)
+{
+    if (!b_conn)
+        return false;
+    struct evbuffer *buf = bufferevent_get_output(b_conn);
+    if (!buf)
+        return false;
+    evbuffer_add(buf, cmd.data(), cmd.size());
+    evbuffer_add(buf, "\r\n", 2);
+    reply_handlers.push_back(reply_handler);
+    return true;
+}
+
+/****** General parsing utilities ********/
+
+/* Split reply line in the form 'AUTH METHODS=...' into a type
+ * 'AUTH' and arguments 'METHODS=...'.
+ * Grammar is implicitly defined in https://spec.torproject.org/control-spec by
+ * the server reply formats for PROTOCOLINFO (S3.21) and AUTHCHALLENGE (S3.24).
+ */
+static std::pair<std::string,std::string> SplitTorReplyLine(const std::string &s)
+{
+    size_t ptr=0;
+    std::string type;
+    while (ptr < s.size() && s[ptr] != ' ') {
+        type.push_back(s[ptr]);
+        ++ptr;
+    }
+    if (ptr < s.size())
+        ++ptr; // skip ' '
+    return make_pair(type, s.substr(ptr));
+}
+
+/** Parse reply arguments in the form 'METHODS=COOKIE,SAFECOOKIE COOKIEFILE=".../control_auth_cookie"'.
+ * Returns a map of keys to values, or an empty map if there was an error.
+ * Grammar is implicitly defined in https://spec.torproject.org/control-spec by
+ * the server reply formats for PROTOCOLINFO (S3.21), AUTHCHALLENGE (S3.24),
+ * and ADD_ONION (S3.27). See also sections 2.1 and 2.3.
+ */
+static std::map<std::string,std::string> ParseTorReplyMapping(const std::string &s)
+{
+    std::map<std::string,std::string> mapping;
+    size_t ptr=0;
+    while (ptr < s.size()) {
+        std::string key, value;
+        while (ptr < s.size() && s[ptr] != '=' && s[ptr] != ' ') {
+            key.push_back(s[ptr]);
+            ++ptr;
+        }
+        if (ptr == s.size()) // unexpected end of line
+            return std::map<std::string,std::string>();
+        if (s[ptr] == ' ') // The remaining string is an OptArguments
+            break;
+        ++ptr; // skip '='
+        if (ptr < s.size() && s[ptr] == '"') { // Quoted string
+            ++ptr; // skip opening '"'
+            bool escape_next = false;
+            while (ptr < s.size() && (escape_next || s[ptr] != '"')) {
+                escape_next = (s[ptr] == '\\');
+                value.push_back(s[ptr]);
+                ++ptr;
+            }
+            if (ptr == s.size()) // unexpected end of line
+                return std::map<std::string,std::string>();
+            ++ptr; // skip closing '"'
+            /* TODO: unescape value - according to the spec this depends on the
+             * context, some strings use C-LogPrintf style escape codes, some
+             * don't. So may be better handled at the call site.
+             */
+        } else { // Unquoted value. Note that values can contain '=' at will, just no spaces
+            while (ptr < s.size() && s[ptr] != ' ') {
+                value.push_back(s[ptr]);
+                ++ptr;
+            }
+        }
+        if (ptr < s.size() && s[ptr] == ' ')
+            ++ptr; // skip ' ' after key=value
+        mapping[key] = value;
+    }
+    return mapping;
+}
+
+/** Read full contents of a file and return them in a std::string.
+ * Returns a pair <status, string>.
+ * If an error occured, status will be false, otherwise status will be true and the data will be returned in string.
+ *
+ * @param maxsize Puts a maximum size limit on the file that is read. If the file is larger than this, truncated data
+ *         (with len > maxsize) will be returned.
+ */
+static std::pair<bool,std::string> ReadBinaryFile(const std::string &filename, size_t maxsize=std::numeric_limits<size_t>::max())
+{
+    FILE *f = fopen(filename.c_str(), "rb");
+    if (f == NULL)
+        return std::make_pair(false,"");
+    std::string retval;
+    char buffer[128];
+    size_t n;
+    while ((n=fread(buffer, 1, sizeof(buffer), f)) > 0) {
+        // Check for reading errors so we don't return any data if we couldn't
+        // read the entire file (or up to maxsize)
+        if (ferror(f))
+            return std::make_pair(false,"");
+        retval.append(buffer, buffer+n);
+        if (retval.size() > maxsize)
+            break;
+    }
+    fclose(f);
+    return std::make_pair(true,retval);
+}
+
+/** Write contents of std::string to a file.
+ * @return true on success.
+ */
+static bool WriteBinaryFile(const std::string &filename, const std::string &data)
+{
+    FILE *f = fopen(filename.c_str(), "wb");
+    if (f == NULL)
+        return false;
+    if (fwrite(data.data(), 1, data.size(), f) != data.size()) {
+        fclose(f);
+        return false;
+    }
+    fclose(f);
+    return true;
+}
+
+/****** Bitcoin specific TorController implementation ********/
+
+/** Controller that connects to Tor control socket, authenticate, then create
+ * and maintain a ephemeral hidden service.
+ */
+class TorController
+{
+public:
+    TorController(struct event_base* base, const std::string& target);
+    ~TorController();
+
+    /** Get name fo file to store private key in */
+    std::string GetPrivateKeyFile();
+
+    /** Reconnect, after getting disconnected */
+    void Reconnect();
+private:
+    struct event_base* base;
+    std::string target;
+    TorControlConnection conn;
+    std::string private_key;
+    std::string service_id;
+    bool reconnect;
+    struct event *reconnect_ev;
+    float reconnect_timeout;
+    CService service;
+    /** Cooie for SAFECOOKIE auth */
+    std::vector<uint8_t> cookie;
+    /** ClientNonce for SAFECOOKIE auth */
+    std::vector<uint8_t> clientNonce;
+
+    /** Callback for ADD_ONION result */
+    void add_onion_cb(TorControlConnection& conn, const TorControlReply& reply);
+    /** Callback for AUTHENTICATE result */
+    void auth_cb(TorControlConnection& conn, const TorControlReply& reply);
+    /** Callback for AUTHCHALLENGE result */
+    void authchallenge_cb(TorControlConnection& conn, const TorControlReply& reply);
+    /** Callback for PROTOCOLINFO result */
+    void protocolinfo_cb(TorControlConnection& conn, const TorControlReply& reply);
+    /** Callback after successful connection */
+    void connected_cb(TorControlConnection& conn);
+    /** Callback after connection lost or failed connection attempt */
+    void disconnected_cb(TorControlConnection& conn);
+
+    /** Callback for reconnect timer */
+    static void reconnect_cb(evutil_socket_t fd, short what, void *arg);
+};
+
+TorController::TorController(struct event_base* baseIn, const std::string& target):
+    base(baseIn),
+    target(target), conn(base), reconnect(true), reconnect_ev(0),
+    reconnect_timeout(RECONNECT_TIMEOUT_START)
+{
+    reconnect_ev = event_new(base, -1, 0, reconnect_cb, this);
+    if (!reconnect_ev)
+        LogPrintf("tor: Failed to create event for reconnection: out of memory?\n");
+    // Start connection attempts immediately
+    if (!conn.Connect(target, boost::bind(&TorController::connected_cb, this, _1),
+         boost::bind(&TorController::disconnected_cb, this, _1) )) {
+        LogPrintf("tor: Initiating connection to Tor control port %s failed\n", target);
+    }
+    // Read service private key if cached
+    std::pair<bool,std::string> pkf = ReadBinaryFile(GetPrivateKeyFile());
+    if (pkf.first) {
+        LogPrint("tor", "tor: Reading cached private key from %s\n", GetPrivateKeyFile());
+        private_key = pkf.second;
+    }
+}
+
+TorController::~TorController()
+{
+    if (reconnect_ev) {
+        event_free(reconnect_ev);
+        reconnect_ev = 0;
+    }
+    if (service.IsValid()) {
+        RemoveLocal(service);
+    }
+}
+
+void TorController::add_onion_cb(TorControlConnection& conn, const TorControlReply& reply)
+{
+    if (reply.code == 250) {
+        LogPrint("tor", "tor: ADD_ONION successful\n");
+        BOOST_FOREACH(const std::string &s, reply.lines) {
+            std::map<std::string,std::string> m = ParseTorReplyMapping(s);
+            std::map<std::string,std::string>::iterator i;
+            if ((i = m.find("ServiceID")) != m.end())
+                service_id = i->second;
+            if ((i = m.find("PrivateKey")) != m.end())
+                private_key = i->second;
+        }
+        if (service_id.empty()) {
+            LogPrintf("tor: Error parsing ADD_ONION parameters:\n");
+            for (const std::string &s : reply.lines) {
+                LogPrintf("    %s\n", SanitizeString(s));
+            }
+            return;
+        }
+
+        service = CService(service_id+".onion", GetListenPort(), false);
+        LogPrintf("tor: Got service ID %s, advertizing service %s\n", service_id, service.ToString());
+        if (WriteBinaryFile(GetPrivateKeyFile(), private_key)) {
+            LogPrint("tor", "tor: Cached service private key to %s\n", GetPrivateKeyFile());
+        } else {
+            LogPrintf("tor: Error writing service private key to %s\n", GetPrivateKeyFile());
+        }
+        AddLocal(service, LOCAL_MANUAL);
+        // ... onion requested - keep connection open
+    } else if (reply.code == 510) { // 510 Unrecognized command
+        LogPrintf("tor: Add onion failed with unrecognized command (You probably need to upgrade Tor)\n");
+    } else {
+        LogPrintf("tor: Add onion failed; error code %d\n", reply.code);
+    }
+}
+
+void TorController::auth_cb(TorControlConnection& conn, const TorControlReply& reply)
+{
+    if (reply.code == 250) {
+        LogPrint("tor", "tor: Authentication successful\n");
+
+        // Now that we know Tor is running setup the proxy for onion addresses
+        // if -onion isn't set to something else.
+        if (GetArg("-onion", "") == "") {
+            proxyType addrOnion = proxyType(CService("127.0.0.1", 9050), true);
+            SetProxy(NET_TOR, addrOnion);
+            SetLimited(NET_TOR, false);
+        }
+
+        // Finally - now create the service
+        if (private_key.empty()) // No private key, generate one
+            private_key = "NEW:RSA1024"; // Explicitly request RSA1024 - see issue #9214
+        // Request hidden service, redirect port.
+        // Note that the 'virtual' port doesn't have to be the same as our internal port, but this is just a convenient
+        // choice.  TODO; refactor the shutdown sequence some day.
+        conn.Command(strprintf("ADD_ONION %s Port=%i,127.0.0.1:%i", private_key, GetListenPort(), GetListenPort()),
+            boost::bind(&TorController::add_onion_cb, this, _1, _2));
+    } else {
+        LogPrintf("tor: Authentication failed\n");
+    }
+}
+
+/** Compute Tor SAFECOOKIE response.
+ *
+ *    ServerHash is computed as:
+ *      HMAC-SHA256("Tor safe cookie authentication server-to-controller hash",
+ *                  CookieString | ClientNonce | ServerNonce)
+ *    (with the HMAC key as its first argument)
+ *
+ *    After a controller sends a successful AUTHCHALLENGE command, the
+ *    next command sent on the connection must be an AUTHENTICATE command,
+ *    and the only authentication string which that AUTHENTICATE command
+ *    will accept is:
+ *
+ *      HMAC-SHA256("Tor safe cookie authentication controller-to-server hash",
+ *                  CookieString | ClientNonce | ServerNonce)
+ *
+ */
+static std::vector<uint8_t> ComputeResponse(const std::string &key, const std::vector<uint8_t> &cookie,  const std::vector<uint8_t> &clientNonce, const std::vector<uint8_t> &serverNonce)
+{
+    CHMAC_SHA256 computeHash((const uint8_t*)key.data(), key.size());
+    std::vector<uint8_t> computedHash(CHMAC_SHA256::OUTPUT_SIZE, 0);
+    computeHash.Write(begin_ptr(cookie), cookie.size());
+    computeHash.Write(begin_ptr(clientNonce), clientNonce.size());
+    computeHash.Write(begin_ptr(serverNonce), serverNonce.size());
+    computeHash.Finalize(begin_ptr(computedHash));
+    return computedHash;
+}
+
+void TorController::authchallenge_cb(TorControlConnection& conn, const TorControlReply& reply)
+{
+    if (reply.code == 250) {
+        LogPrint("tor", "tor: SAFECOOKIE authentication challenge successful\n");
+        std::pair<std::string,std::string> l = SplitTorReplyLine(reply.lines[0]);
+        if (l.first == "AUTHCHALLENGE") {
+            std::map<std::string,std::string> m = ParseTorReplyMapping(l.second);
+            if (m.empty()) {
+                LogPrintf("tor: Error parsing AUTHCHALLENGE parameters: %s\n", SanitizeString(l.second));
+                return;
+            }
+            std::vector<uint8_t> serverHash = ParseHex(m["SERVERHASH"]);
+            std::vector<uint8_t> serverNonce = ParseHex(m["SERVERNONCE"]);
+            LogPrint("tor", "tor: AUTHCHALLENGE ServerHash %s ServerNonce %s\n", HexStr(serverHash), HexStr(serverNonce));
+            if (serverNonce.size() != 32) {
+                LogPrintf("tor: ServerNonce is not 32 bytes, as required by spec\n");
+                return;
+            }
+
+            std::vector<uint8_t> computedServerHash = ComputeResponse(TOR_SAFE_SERVERKEY, cookie, clientNonce, serverNonce);
+            if (computedServerHash != serverHash) {
+                LogPrintf("tor: ServerHash %s does not match expected ServerHash %s\n", HexStr(serverHash), HexStr(computedServerHash));
+                return;
+            }
+
+            std::vector<uint8_t> computedClientHash = ComputeResponse(TOR_SAFE_CLIENTKEY, cookie, clientNonce, serverNonce);
+            conn.Command("AUTHENTICATE " + HexStr(computedClientHash), boost::bind(&TorController::auth_cb, this, _1, _2));
+        } else {
+            LogPrintf("tor: Invalid reply to AUTHCHALLENGE\n");
+        }
+    } else {
+        LogPrintf("tor: SAFECOOKIE authentication challenge failed\n");
+    }
+}
+
+void TorController::protocolinfo_cb(TorControlConnection& conn, const TorControlReply& reply)
+{
+    if (reply.code == 250) {
+        std::set<std::string> methods;
+        std::string cookiefile;
+        /*
+         * 250-AUTH METHODS=COOKIE,SAFECOOKIE COOKIEFILE="/home/x/.tor/control_auth_cookie"
+         * 250-AUTH METHODS=NULL
+         * 250-AUTH METHODS=HASHEDPASSWORD
+         */
+        BOOST_FOREACH(const std::string &s, reply.lines) {
+            std::pair<std::string,std::string> l = SplitTorReplyLine(s);
+            if (l.first == "AUTH") {
+                std::map<std::string,std::string> m = ParseTorReplyMapping(l.second);
+                std::map<std::string,std::string>::iterator i;
+                if ((i = m.find("METHODS")) != m.end())
+                    boost::split(methods, i->second, boost::is_any_of(","));
+                if ((i = m.find("COOKIEFILE")) != m.end())
+                    cookiefile = i->second;
+            } else if (l.first == "VERSION") {
+                std::map<std::string,std::string> m = ParseTorReplyMapping(l.second);
+                std::map<std::string,std::string>::iterator i;
+                if ((i = m.find("Tor")) != m.end()) {
+                    LogPrint("tor", "tor: Connected to Tor version %s\n", i->second);
+                }
+            }
+        }
+        BOOST_FOREACH(const std::string &s, methods) {
+            LogPrint("tor", "tor: Supported authentication method: %s\n", s);
+        }
+        // Prefer NULL, otherwise SAFECOOKIE. If a password is provided, use HASHEDPASSWORD
+        /* Authentication:
+         *   cookie:   hex-encoded ~/.tor/control_auth_cookie
+         *   password: "password"
+         */
+        std::string torpassword = GetArg("-torpassword", "");
+        if (!torpassword.empty()) {
+            if (methods.count("HASHEDPASSWORD")) {
+                LogPrint("tor", "tor: Using HASHEDPASSWORD authentication\n");
+                boost::replace_all(torpassword, "\"", "\\\"");
+                conn.Command("AUTHENTICATE \"" + torpassword + "\"", boost::bind(&TorController::auth_cb, this, _1, _2));
+            } else {
+                LogPrintf("tor: Password provided with -torpassword, but HASHEDPASSWORD authentication is not available\n");
+            }
+        } else if (methods.count("NULL")) {
+            LogPrint("tor", "tor: Using NULL authentication\n");
+            conn.Command("AUTHENTICATE", boost::bind(&TorController::auth_cb, this, _1, _2));
+        } else if (methods.count("SAFECOOKIE")) {
+            // Cookie: hexdump -e '32/1 "%02x""\n"'  ~/.tor/control_auth_cookie
+            LogPrint("tor", "tor: Using SAFECOOKIE authentication, reading cookie authentication from %s\n", cookiefile);
+            std::pair<bool,std::string> status_cookie = ReadBinaryFile(cookiefile, TOR_COOKIE_SIZE);
+            if (status_cookie.first && status_cookie.second.size() == TOR_COOKIE_SIZE) {
+                // conn.Command("AUTHENTICATE " + HexStr(status_cookie.second), boost::bind(&TorController::auth_cb, this, _1, _2));
+                cookie = std::vector<uint8_t>(status_cookie.second.begin(), status_cookie.second.end());
+                clientNonce = std::vector<uint8_t>(TOR_NONCE_SIZE, 0);
+                GetRandBytes(&clientNonce[0], TOR_NONCE_SIZE);
+                conn.Command("AUTHCHALLENGE SAFECOOKIE " + HexStr(clientNonce), boost::bind(&TorController::authchallenge_cb, this, _1, _2));
+            } else {
+                if (status_cookie.first) {
+                    LogPrintf("tor: Authentication cookie %s is not exactly %i bytes, as is required by the spec\n", cookiefile, TOR_COOKIE_SIZE);
+                } else {
+                    LogPrintf("tor: Authentication cookie %s could not be opened (check permissions)\n", cookiefile);
+                }
+            }
+        } else if (methods.count("HASHEDPASSWORD")) {
+            LogPrintf("tor: The only supported authentication mechanism left is password, but no password provided with -torpassword\n");
+        } else {
+            LogPrintf("tor: No supported authentication method\n");
+        }
+    } else {
+        LogPrintf("tor: Requesting protocol info failed\n");
+    }
+}
+
+void TorController::connected_cb(TorControlConnection& conn)
+{
+    reconnect_timeout = RECONNECT_TIMEOUT_START;
+    // First send a PROTOCOLINFO command to figure out what authentication is expected
+    if (!conn.Command("PROTOCOLINFO 1", boost::bind(&TorController::protocolinfo_cb, this, _1, _2)))
+        LogPrintf("tor: Error sending initial protocolinfo command\n");
+}
+
+void TorController::disconnected_cb(TorControlConnection& conn)
+{
+    // Stop advertizing service when disconnected
+    if (service.IsValid())
+        RemoveLocal(service);
+    service = CService();
+    if (!reconnect)
+        return;
+
+    LogPrint("tor", "tor: Not connected to Tor control port %s, trying to reconnect\n", target);
+
+    // Single-shot timer for reconnect. Use exponential backoff.
+    struct timeval time = MillisToTimeval(int64_t(reconnect_timeout * 1000.0));
+    if (reconnect_ev)
+        event_add(reconnect_ev, &time);
+    reconnect_timeout *= RECONNECT_TIMEOUT_EXP;
+}
+
+void TorController::Reconnect()
+{
+    /* Try to reconnect and reestablish if we get booted - for example, Tor
+     * may be restarting.
+     */
+    if (!conn.Connect(target, boost::bind(&TorController::connected_cb, this, _1),
+         boost::bind(&TorController::disconnected_cb, this, _1) )) {
+        LogPrintf("tor: Re-initiating connection to Tor control port %s failed\n", target);
+    }
+}
+
+std::string TorController::GetPrivateKeyFile()
+{
+    return (GetDataDir() / "onion_private_key").string();
+}
+
+void TorController::reconnect_cb(evutil_socket_t fd, short what, void *arg)
+{
+    TorController *self = (TorController*)arg;
+    self->Reconnect();
+}
+
+/****** Thread ********/
+static struct event_base *gBase;
+static boost::thread torControlThread;
+
+static void TorControlThread()
+{
+    TorController ctrl(gBase, GetArg("-torcontrol", DEFAULT_TOR_CONTROL));
+
+    event_base_dispatch(gBase);
+}
+
+void StartTorControl(boost::thread_group& threadGroup, CScheduler& scheduler)
+{
+    assert(!gBase);
+#ifdef WIN32
+    evthread_use_windows_threads();
+#else
+    evthread_use_pthreads();
+#endif
+    gBase = event_base_new();
+    if (!gBase) {
+        LogPrintf("tor: Unable to create event_base\n");
+        return;
+    }
+
+    torControlThread = boost::thread(boost::bind(&TraceThread<void (*)()>, "torcontrol", &TorControlThread));
+}
+
+void InterruptTorControl()
+{
+    if (gBase) {
+        LogPrintf("tor: Thread interrupt\n");
+        event_base_loopbreak(gBase);
+    }
+}
+
+void StopTorControl()
+{
+    if (gBase) {
+        torControlThread.join();
+        event_base_free(gBase);
+        gBase = 0;
+    }
+}
+
diff --git a/src/torcontrol.h b/src/torcontrol.h
new file mode 100644
index 000000000..72dc82c5b
--- /dev/null
+++ b/src/torcontrol.h
@@ -0,0 +1,20 @@
+// Copyright (c) 2015 The Bitcoin Core developers
+// Distributed under the MIT software license, see the accompanying
+// file COPYING or http://www.opensource.org/licenses/mit-license.php.
+
+/**
+ * Functionality for communicating with Tor.
+ */
+#ifndef BITCOIN_TORCONTROL_H
+#define BITCOIN_TORCONTROL_H
+
+#include "scheduler.h"
+
+extern const std::string DEFAULT_TOR_CONTROL;
+static const bool DEFAULT_LISTEN_ONION = true;
+
+void StartTorControl(boost::thread_group& threadGroup, CScheduler& scheduler);
+void InterruptTorControl();
+void StopTorControl();
+
+#endif /* BITCOIN_TORCONTROL_H */